Gramophone



T. DRISCOLL Sept. 11, 1923.

enamornona Filed April 20,. 922

Patented Sept. 11, 1923.

TES

U l T E S T TIMOTHY nnIscoLL, or Lonnoiv, NGLAni).

GRAMOPHONE.

Application filed April 20, 1922. Serial No. 555,667.

To all whom it may concern:

Be it known that I, TIMOTHY DRISCOLL, a subject of the King of Great Britain, residing at London, England, have invented. certain new and useful Improvements in Gramophones, of which the following is a specification.

My invention relates to gramophones.

In a gramophone fitted with an all-wood tone-arm, for example, owing to the small vertical lift of the tone-arm difliculty, is experienced it the insertion or removal of the needles is attempted without rotating the sound box, while the finger of the operator is liable to be pricked during the operation. If the sound box is rotated to facilitate the insertion of the needles, its position is required to be adjusted after each insertion, so that the needle lies at the correct angle to the record; I

The object of my invention is to provide an improved arrangement of tone-arm and sound box suitable for the above and other types of gramophones, in which the above disadvantages are obviated, and the replacement of the needles is effected in a simple and expeditious manner.

My invention consists in an arrangement of sound box and tone-arm in which one of these parts may be rotated relatively to the other, for the insertion or removal of nee-- dles, means being provided for automatically registering and locking the parts in the operative position.

My invention further consists in a connect-ion, union or the like adapted to be secured to the tone-arm and having a rotat-- ably mounted member adapted to carry the.

sound box, means being provided for automatically locking the rotatable member in one or more positions.

My invention also consists in the improved arrangement of tone-arm and sound box, and connection therefor, to be hereinafter described.

Figure 1 shows an elevation of a tone arm and sound box for a gramophone pro vided with my invention.

Figure 2 shows an elevation on an enlarged scale of the connection between the tone-arm and sound-box, while Figure 3 shows a longitudinal section of the same.

Figure 4 shows a cross section of the connection, the section being taken on the line IV-IV Figure 3.-

Figures 5, 6 and parts forming the connection.

In carrying my invention. into efieot according to one form and as applied by way of example to a gramophone provided with a tone-arm of the all-wood type, I attach to the sound box end of the tone-arm 1,*

Figure 1, a ring 2 of brass or other suit'able material. This ring is provided at lts rear end wlth a recess or groove 3, Figure 3,-1nto which the end of the tone-arm 1 fits, while. "the forward end of the ring 2, is of reduced diameter to accommodate an external1y disposed split spring-ring 4, Figures 2-, 3,- 4

and 6 In the reduced portion two holes 5 -and '6, Figures 3, 4 and 5 are formed intowhich balls 7 and 8 respectively are inserted. These balls are adapted tobe retaine'd' 'in position by the spring-ring 4, in such a manner, that a portion of the balls project beyond the inner periphery of the ring 2.

7 show elevations of the Within the ring 2 an annular member 9, iv

In assembling the parts the spring-ring 4 is rotated until one of the holes, for example the hole 5, registers with the split in the spring-ring. The annular member 9 is then inserted in the ring 2 and the ball 7 inserted into the hole 5. The spring-ring 4 is then rotated until the split registers with the hole 6 when the ball 8 is inserted and the spring-ring rotated so that both the balls are pressed into the groove 11.

The holes 5 and 6 are spaced apart to correspond to the operative and upturned positions of the needle holder 16, as shown in Figure 1. The annular member 9 may be easily rota-- ted except when either of the balls .7 and 8 register with the spherical depression or hole 12, in which positions a considerable force must be exerted to rotate the annular member 9, past these points so that in these positions it is practically locked.

The sound box 15 is secured in the annular member 9 by means of the screw 14 be fore described, and in such a position that when the needle is in the operative position, the ball 7 registers with the depression or hole 12 in the groove 11, of the annular member 9.

When it is desired to change the needle, the sound box 15 and the attached annular member 9, are rotated until the ball registers with the depression or hole 12 when the holder for the needle is in a more or less upright position shown-in dotted lines on Figure 1. The needle is then inserted and the sound box 15 rotated in the reverse direction, until the ball 7 springs into the depression or hole 12 and locks the sound box in the operative position of the needle.

In some cases I may dispense withone ot the balls above described and arrange the ring 2 with a. single ball which locks the anjnular member in the operative positiomot' the needle only, or I may use one ball-in eonjunction with two depressions spaced apart on the annular member so as to lock the sound box in the operative and upturned position of the needle holder.

By means of my invention it will be seen that needles may be inserted or removed in a very convenient and simple manner, while the sound box is automatically registered and locked whenever the operative position parting beyond the scope of my invention.

I claim: A tone arm havlng. a circumferentially reduced extremity formed with an opening therethrougli, a sound box carrying memberrotatably mounted in said. extremity and having an annular groove with which said opening is in registry, a ball loosely seated in said opening and riding in said groove, said member having an opening within the groove to receive the ball in a certain relative position of the member and tone arm, and a spring band slidably fitting said extremity and overlying and bearing on said. ball, the ends of said band being spaced apart to permit insertion or withdrawal. of said ball at will.

In testimony whereof I have signed my name to this specification.

TIMOTHY DRIS COLL. 

